Ruby Issue Tracking System

01/04/2026

03:53 AM Ruby Revision ca0fece5 (git): [DOC] Tweak an example in language/box.md

Although the example code comments indicate that it returns `false`,
a non-matching result for `=~` is actually `nil`.
```ruby
Foo.foo.blank? #=> false
"foo".blank? #=> false
```
https://github.com/ruby/ruby/blob/v4.0.0-preview3/doc/... koic (Koichi ITO)

03:52 AM Ruby Revision d8d41d74 (git): [DOC] Use `Ruby::Box#require_relative` in box.md examples

Based on the example, it appears that `foo.rb` and `main.rb` are expected to be in the same directory.
Since Ruby 1.9, the current directory is not included in `$LOAD_PATH` by default.
As a result, running `box.require('foo')` as shown i... koic (Koichi ITO)

12/26/2025

02:00 AM Ruby Revision f3149af3 (git): [ruby/prism] Sync `Prism::Translation::ParserCurrent` with Ruby 4.0

This PR updates the fallback version for `Prism::Translation::ParserCurrent` from 3.4 to 4.0.
Currently, the fallback resolves to `Parser34`, as shown below:
```console
$ ruby -v -rprism -rprism/translation/parser_current -e 'p Prism::... koic (Koichi ITO)

12/25/2025

02:56 PM Ruby Misc #21804 (Closed): Getting setup-ruby Earlier

ruby/setup-ruby is commonly used for development in OSS projects and real-world Rails applications.
https://github.com/ruby/setup-ruby
This is not specific to Ruby 4.0.0. There is often a delay between a Ruby release and the availabi... koic (Koichi ITO)

12/22/2025

06:38 AM Ruby Bug #21799 (Closed): Delegated top-level methods are not visible outside the Ruby Box

The following example code based on Ruby Box results in an unexpected error.
https://github.com/ruby/ruby/blob/v4.0.0-preview3/doc/language/box.md#top-level-methods
I'm not familiar with Ruby Box, but it seems that either the above d... koic (Koichi ITO)

06/02/2025

03:29 AM Ruby Feature #21393: One-line pattern matching syntax as a method argument

> That code is not a pattern matching. It is interpreted as a keyword argument.
Oops! This was entirely my misunderstanding. koic (Koichi ITO)

03:00 AM Ruby Feature #21393 (Feedback): One-line pattern matching syntax as a method argument

## Context
Using one-line `in` pattern matching syntax as a method argument causes a syntax error.
```console
$ ruby -vce 'do_something(expression in pattern)'
ruby 3.4.4 (2025-05-14 revision a38531fd3f) +PRISM [x86_64-darwin24]
... koic (Koichi ITO)

05/14/2025

04:57 AM Ruby Bug #21337 (Closed): Using `not` on the RHS of a logical operator becomes valid syntax with Prism

The following syntax behavior differs between Ruby 3.3 (parse.y by default) and Ruby 3.4 (Prism by default).
```ruby
if true && not true; end
```
## Expected
In Ruby 3.3 and earlier, the following code results in a syntax erro... koic (Koichi ITO)

03/10/2025

04:57 PM Ruby Revision 6b4453e3 (git): [ruby/prism] Support `itblock` for `Prism::Translation::Parser`

## Summary
`itblock` node is added to support the `it` block parameter syntax introduced in Ruby 3.4.
```console
$ ruby -Ilib -rprism -rprism/translation/parser34 -e 'buffer = Parser::Source::Buffer.new("path"); buffer.source = "proc {... koic (Koichi ITO)

10:19 AM Ruby Revision f4c16c57 (git): [ruby/optparse] Make the result of `tty?` obtainable with flexible stdout

In mock testing for stdout, `StringIO.new` is sometimes used to redirect the output.
In such cases, the assignment is done with `$stdout = StringIO.new`, not the constant `STDOUT`.
e.g., https://github.com/rubocop/rubocop/blob/v1.71.1/li... koic (Koichi ITO)